Any competent gun smith can probably reduce the trigger pull and polish internals on the FSN, but it's finding one to do it on the FSN is another story. EA is the only regular Joes in town that do it. There's a YT that shows 3lb reduction in trigger pull.
I just had my USG done by EA ! It was worth every penny! They were fast one month turn around. Every thing as promised! If you go this route be sure to get the aftermarket trigger and spring they make a world of difference.